Era Score, Civilization Collapse, and Existential Risks

With the new Era Score system for R&F, I've been wondering if a future expansion should include a threshold below Dark Age that prompts a "Collapse" if it is not passed. Collapse would be as drastic as it sounds, and it would simply wipe out any civilization unfortunate enough not to hit the next threshold.

This would be coupled with negative Era events that would actually reduce your Era score. In particular, I was thinking of new existential threats that could threaten the entire globe near the end of the tech tree. Since the game tends to get a bit dull towards the end when you've more or less eliminated the threat of your competitors achieving a victory before you, existential threats like global warming, hostile AI, pandemic, etc. could be a good way to keep up the tension. Unlocking late era techs would be necessary for achieving a Space Race victory, but they would also increase the risk of some of these existential threats for all players.

Threats might emerge in one civilization and spill into the next. Players would have to make investments to avoid or mitigate the damage of these threats. In this case, rather than the victory screen appearing immediately after the victory conditions are met, the winning player would have to trigger a victory condition and survive to the end of the Era with an Era score above the Collapse threshold.